1. Field of the Invention
The present invention relates to an envelope waveform generator circuit to which a touch response is added.
2. Description of the Prior Art
In the prior art electronic musical instruments, systems for controlling turn-on and turn-off envelope waveforms of musical note signals generally used include a system for applying a charge and discharge voltage of a time constant circuit composed of capacitors and resistors to a gate circuit to thereby to control the gate circuit by opening and closing thereof.
In the system as described above, however, it has been impossible to provide a suitable envelope control having a touch response and difficult to provide integration.
In alternative systems, there is proposed a system for directly reading out an envelope waveform memory subjected to digital sampling. This system, however, poses disadvantages such that quantitized noises are increased and in order to eliminate thereof, a memory capacity must be increased, which requires more elements in number, and particularly in case where the touch response is desired to be added, a number of circuits are required and on the other hand, controlling becomes extremely complicated.